Chusetts



y 1931. F. H. LAHEY 1,806,808

FORCEPS Filed Dec. 28, 1928 muullllllllllllllllll"NHIHHIIIIIIIIIHI Fatented May 26, 1931 UNITED STATES PATENT- OFFICE FRANK H. LAHEY, OF BOSTON, MASSACH U-SETTS, ASSIGNOR TO NEW ENGLAND DEACONESS ASSOCAEATION, F BOSTON, MASSACHUSETTS, A CORPORATION OF MASSA- roncnrs I Application filed December 28; 1928. Serial No. 328,877.

This invention relates to surgeons forceps andligators. The main objects are to overcome and avoid certain structural defects and also .thosedifliculties in use which have generally characterized such instruments; and more particularly toprovide an improved form of pivotal X-joint therefor adapted to 'assure against sutures and liga- 'bers, apart from tures: catching. on the joint when the instrument is in use, and also adapted to compensate for wear and rust, and at all times to assure a tight joint especially when. the instrument is set, as in use, and ever to assure m-utual'registry of the j awtips when closed.

Heretoiiore such instruments have sometimes caused much inconvenience to surgeons on account of the ligatures or sutures catching on shoulders or crevices at the joint, especially when the instrument has been in service a long time and has become worn or corroded at the joint, as is inevitable, due in part to frequent sterilizing. In applying ligatures, for instance, the thread is usually caused to slide over the instrument, past the X-joint and down toward the tips of the jaws, and any chance to catch at the joint causes trouble and loss of precious time, especially in difficult operations. Furthermore, looseness at the joint, as from wear, tends to let the jaws slip sidewise out of precise registry; and this may result in uncertain holding power of the instrument and consequent annoyance and trouble.

An illustrativeembodiment of th-is'invention'is shown by the accompanying drawings in which t Figure 1' is a plan of a device embodying this invention.

I closed.

. Fig.3 is a plan ofoneof the leverage memthe complementary. mem-' ber. 1 I

.Fig. 4 is an inner face view of themember shown in Fig. 3.

Fig. is similar to Fig. 3 except that it shows the reverse side of the memberre- .ferred to.

Fig. 6 is an enlarged section on the line 66 of Fig. 2.

Fig. 7 isa section on the line 77 of Fig. 2.

Fig. 8 is a right end view of the handle and latch means. shown in Fig. 1.

The forceps device here shown is of the pincers type and comprises a pair of complementary leverage members land 2 fastened together pivotally as by the screw 3. Handle rings 4 and 5 are formed, on the outer ends of the long resilient arms to accommodate manipulation scissorswise by the thumb and fingers. In order to secure the forceps automatically in their set closed position, adjustable catch or pawl and ratchet means 6' and 7 are formed adjacent to the handles band 5. The jaws 8 and 9 are provided with rough faces as at 10 to positively grip the tissues or blood vesselswhen in use. v

Inorder to accommodate the main pur poses herein referred to, the members 1 and 2 are medially notched, as at 11, at their point of pivotal connection and each member is formed with inclined joint surfaces for wedging engagement, relative to the complementary member, on both the handle and jaw sides of the pivot 3. These parts are so formed as to avoid any shoulders, hook parts or crevices capable of engaging or snagging any ligatures, as will be apparent from the appropriately inclined faces of the joint members illustrated in the drawings. Preferably'these notches 11 are exactly similar, and the members 1 and 2 are substantially alike in every way at and adjacent to the joint, except that'the pivot bore of one is threaded with a slight countersink for riveting, as at 12', and that of "the other'is plain and is more countersunk to accommodate the head of screw 3 as at 13.

Each notch 11 is formed with a plainshear bearing surface 14 at the bottom, perpendicular to the pivot 3. Surface 14 is flanked in part by notch end surfaces 15 and 16 which are inclined outwardly therefrom toward the corresponding jaw, and in part by surfaces 17 and 18 which are inclined outwardly therefrom oppositely from the notch and toward the corresponding j aw. V Said surfaces 15 and 16 intersect face 14 on parallel lines and preferably are themselves mutually parallel; and likewise as. to surfaces 17 and 18.

On both members 1 and 2 each surface 15, 16, 17 and 18 is inclined outwardlyfrom surface 14 tovard the corresponding aw 8, and the resultant acute angles all face or open toward said jaws. i

The faces 16 and 18 form slightly obtuse and preferably like angles relative to the jaw face 10, and the outer ends of the edge lines 19, 20, 21 and 22 are tangent to a circle concentric with pivot This provides for mutual wedging action sufficient to assure a tight fit when the instrument is set, even after much use and wear, mutual contacts occurring at faces 16 and 18 on members 1 and 2 respectively and likewise for faces 17 and 15.

The inclination of face 15 results in a corresponding overlap by the body part 23 which diminishes toward the corresponding jaw.

The pivot 8 is formed as a screw to facilitate assembly, but its tip is riveted at 2 1 to prevent working loose, and the members 1 and 2 are countersunk to accommodate the head 25 and said part 24, the pivot ends then being entirely flush with the surface of the forceps.

As a result of the foregoing, all joint surfaces, except the two shear surfaces 14, slant outwardly and toward the jaws, and all transverse lines extend diagonally, as at 26 and 27, in conseqeunce of which no shoulders or crevices exist on which any ligatures may be caught as they are slid down toward or over the jaws and the instrument is snag proof.

The inclined surfaces and joint lines all tail outwardly and toward the jaw tips and so permit the thread to slide over the oint on its way to the forward end of the instrument. The overhanging rear shoulder faces 15 act somewhat camwise against the opposing faces 17 and this, together with the corresponding action at the faces 16 and 18, forces the members together rigidly when set, even after the pivot or bearing faces or both have become worn or corroded, and so properly alines the jaw tips.

These instruments are used in substantially the same manner as ordinary surgeons forceps, the blood vessel or other tissue being gripped by the jaws 89 when the resilient handle arms are brought together and held set by the lock means 67. But when ligatures are applied, the former tendency to catch at the pivot joint is avoided, all lines and faces thereof being arranged to positively shed the ligatures in the direction of the jaw tips. After the ligatures or sutures are in place, the forceps are removed.

Although but one specific embodiment of this invention is herein shown and described,

it is to be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of the invention as defined by the following claims.

Furthermore this invention is adapted for embodiment in various kinds of surgical and dental instruments wherever a tight joint is desirable, including all kinds of forceps, needle holders and scissors. The form of joint described and claimed assures positive action and a sure grip. It prevents Wabbling of the jaws or blades, even after considerable wear, and even to the very tips, and so ef fects a most desirable and important result.

I claim:

1. A pair of ligaturing forceps the crossed leverage members of which interfit substantially flush with each other at the joint and are formed both in front of and back of the pivoted axis each to overlap the other diagonally of the axis of the instrument and so form acute surface contact angles therewith in the direction of the aws, whereby the forceps are snag proof in use.

2. A forceps instrument of the character described comprising a pair of leverage members connected crosswise and having a pivotal X-joint formed with a pair of coacting surfaces disposed perpendicularly to the pivot axis and with all other mutual contact joint surfaces inclined outwardly from the first said surfaces and toward the aws and forming acutes angles opening towards said jaws respectively.

3. A ligator of forceps like character comprising a pair of leverage members pivotally connected X-wise, said members being simlarly apertured for mutual interfit at the point of connection, and each being formed with a contact plane perpendicular to the pivotal axis, and each being formed on the notch side of said plane with end surface contact shoulders inclined to the instrument axis and toward the jaws outwardly from said plane and providing for rigid binding engagement of said members with the aW tips in mutual registry when the device is closed.

4. A pair of forceps the leverage members of which, on the handle side of the pivotal axis, are formed with a pair of coacting shoulders one of which is undercut and overlaps the other to form an acute angle with the instrument axis taken in the direction of the jaws.

5. A pair of forceps, the crossed leverage members of which, on the handle side of the pivotal axis, are formed with mutually coacting shoulders having contact faces inclined to the main plane of the forceps, said shoulders overlapping one another to form acute angles with the instrument axis taken in the direction of the jaws.

6. A pair of forceps, the leverage members of which have coacting faces in a common shear plane adjacent to the pivotal axis, said members, on each side of said plane, on the handle side of said axis, being formed with a pair of coacting shoulders one overla ping the other to form acute angles Wit the instrument axis taken in the direction of the jaws, each pair in a plane respectively which is inclined to said shear plane.

Signed at Boston, Mass, this 19th day of December, 1928.

FRANK H. LAHEY. 

